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Pump is 2", but you can see the 2x1.5 insert adapters in the inlet & outlet.
Oops. Not quite.
The valve is a 1.5" valve with 2" fittings over the valve -- that would reduce suction flow loss on those segments a lot. Pipe from valve to pump is also 2". But, pipe from pump to filter is 1.5".
Sorry.
Actually, I do. In the past couple of weeks, we have been doing some geometry. They have calculated the circumference of my pool, area of my pool floor, surface area of my pool (cylinder), etc. They all wanted to know if they could come over and swim when school is out. Uh............ I don't think all 140 of y'all are gonna fit in my pool!!Quote:
Originally Posted by PoolDoc
Great!
But what about volume, in both SI and US. And weight! Have a bag of M&M's and give it to the person who can best estimate the volume in 60 seconds.
And flow rate, in GPM, LPM and pounds per hour.
And, from the weight of sand in your filter, the average grain size (0.50mm), and the mass density of quartz, and an assumption of a grain shaped like an equilateral 4-sided pyramid (doubled) . . . calculate the number of sand particles in your filter!
Oh boy, Ben. You're gonna be in big trouble! Giving M&Ms is a big NO-NO! We can't give any food out for any reason in our district. No pieces of candy for a reward, no pizza parties for rewards. You can't even do any lessons with actual food. No cooking anything when we study fractions, etc. We might all get fat from those 13 M&Ms in the snack size bag!
Well, offer them a bag of all-natural and extra-healthy crickets instead. That will probably motivate the boys, anyhow . . . especially if you give out the crickets in the first class of the day. :o
PS. Walmart sells them, at least around here.
Just to add my two cents:
In case you haven't figured it out, for now pay no attention to T/A or CH. Don't add any baking soda.
For whatever reason your pH running a little low, in the 7.2 range isn't a problem. Don't "fix" it. Chlorine is actually more effective at lower pH levels and 7.2 is safe for vinyl and safe for swimming.
Carl
Suction piping is 2" from the pool. Dual skimmers, one on the near side and one on the far. Pump is at ground level, no more than 3' from the pool level to the pump, probably less than 2' total. Approximately 20-30 ft between the near skimmer and the pump. Filter pressure is ~20 psi clean and I normally backwash about ~28 psi.
Quote:
Originally Posted by mas985
This sentence is not making sense to me. Is your pump 3' or 2' above the water line (vertical distance)?Quote:
Originally Posted by TheGoose
And YOU buy these, I presume?Quote:
Originally Posted by PoolDoc
Sorry. The vertical distance from the water level to the pump suction. The pump is on a small slab, the pipe rises out of the ground about 12" or so, add in whatever the water level is below that, I would say probably a 2' suction lift. I haven't measured it, but it's pretty minor.
Thanks for all the replies.
Looking back over the thread, one thing I neglected was that you have a top mount filter with a backwash valve. Those valves tend to have fairly high head loss and half of that is before the filter gauge so it is not part of the filter pressure. Anyway if I include that and the suction side plumbing setup including the 3-way valve, here is what I get as an operating point:
Flow Rate (GPM) 69
Head Loss (ft) 65
Energy Use (Watts) 1,839
Energy Factor (Gallons per Watt-Hr) 2.26
Here is the break down of head:
Suction plumbing: 6' = 4' of dynamic head + 2' of static head
Pre-filter backwash valve (1/2): 10' dynamic head
Return plumbing: 49' = 51' of dynamic head - 2' of static head
Hopefully everything is included this time. If you want any more accuracy, you are going to have to take a suction measurement at the pump.
Thanks for your info.
Here's an interesting tid-bit: The low speed amperage is right about 1.0 amp as measured with my digital amp-probe. The full speed amps are ~7 if I recall. I know for a fact that the low speed is 1.0 amps, I measured both legs because that sounded too low.
Thoughts?
The CEC measurements for the Whisperflo show low speed power about 24% of high speed power so that is what I would expect. I would be very surprised in the 1 HP Whisperflo only drew 1 amp on low speed. Are you sure you are not running into any accuracy issues with the amp meter? Can you confirm with the house power meter?
I'm thinking that since I have the pump restricted back and thus the flow lowered that the amps are lower.
As far as accuracy I think the meter is close.
Here's the specs:
HP - 1~.13
RPM - 3450/1725
Volts - 230
Service Factor Amps - 7.4/1.4
Service Factor - 1.65
Frame - 56Y
Shaft - Threaded
Overload Protector - Auto
Length Includ. Shaft - 13.4
So I think ~1 amp is right on the money if the flow is restricted back.
Also I pulled the top off the filter and installed a union. I added 1.5 bags of sand but I really didn't notice the level being low. In fact it was actually quite high. I put about ~75 lbs in just for good measure. I did notice my starting pressure being slightly higher, about 22 psi instead of ~19-20. Will wait and see.
I don't remember you saying anything about this. How have you restricted the pump?Quote:
Originally Posted by TheGoose
Also, I noticed from the picture that you may have one of the suction lines closed. Is that the case and if so, is the 20 PSI clean filter pressure when that port is closed?
Also, what was the model # of your original pump (e.g. WF-4 or WF-24)?
All of these things can make a big difference in the operating point of the pump.
The pump was restricted some by the extra DE in the filter (added per this site)....had it at about 26-28 psi. I heard that a plugged filter actually filters better. Normally I would backwash at this pressure but nothing else seems to work. I was actually running on low speed at ~10 psi, but the filter was close to needing backwashed.
I run with the main drains closed so the skimmers will function better. I have dual main drains with the upgraded covers so it's not really a safety issue. I have a lot of over hanging trees etc. and I need as much skimming as I can get.
The original pump is a WFE-4.
Quote:
Originally Posted by mas985
Ok, I think I understand. The amp measurements were made with the higher pressure but your normal pressure is 20 PSI. Correct? Also, 20 PSI is with a clean filter and one suction port closed, correct?
But I don't believe it is possible for that pump run on low speed at 10 PSI. Max head for that pump on low speed is 22' and 10 PSI would put it well over that including gauge height. Also, if the filter was reading 27 PSI on high speed, it should have read somewhere close to 5 PSI on low speed. So either there is a problem with the pressure gauge or you did not read it correctly.
You're actually correct. The gauge is ranged to like 60 psi but really should only range to 30 psi for better accuracy.
At low range it's running under 10 psi, I believe about 6 psi. When the filter is plugged and the pump is reading about 26-28 psi on high speed it doesn't really change low speed pressure as much. Low speed is still under 10 psi, I believe about 6-8 psi but I haven't looked at it real close. Now that I think about it 6 psi is probably about right.
I was just rounding to 10 psi but it is definitely under that.
Thanks for all your help.
Blue White flow meter in hand. We'll know soon enough about my flow.
Please do.
OK, I just wanted to update this thread. My pool is sparkly clear, and all I have been using is the BBB method and keeping a close watch on the chemistry.
It took the sand filter about 2 weeks to clear the water up once I got the FC up to the right level. I added 10 large jugs of bleach, which brought the FC up to 50+, and then within two days it was between 10-20ppm. After that it went down below 6 ppm, and the water got better every day. I am also a big believer in 2-speed pumps. I run mine on high for 2 hours in the morning and then switch to low for 10 more hours.
Still have not installed the BW flowmeter, it's on my list.
Thanks for all your help.